Envelop.



No. 643,735. Patented Feb. 20, I900.

E. T. STUART.

- ENVELOP.

(Application filed Sept. 27, 1899A (No Model.)

THE NORRIS PETERS co. PRoTo-uma. msnmsmu. n. c.

UNITED STATES PATENT OFFICE.

EDIVIN THOMAS STUART, OF OTTAIVA, KANSAS.

ENVELOPf SPECIFICATION forming part of Letters Patent No. 643,73 5, dated February 20, 1900.

Application filed September 27, 1899. Serial No. 731,888. (No model.)

To all whom it may concern:

Be it known that I, EDWIN THOMAS STUART,

a citizen of the United States, residing at Ottawa, in the county of Franklin and State of Kansas, have invented an Improvement in Envelops, of which the following is a specification, reference being had to the accompanying drawings, showing the parts thereof.

My invention relates to a safety-envelop designed for the safe transmission of its contents through the mails; and the object in View is to provide a simple and cheap construction which will be secured against accidental opening, cannot be surreptitiously opened without detection by steam or other processes, and thereby destroy the utility of the article, and which will have the effect of deterring persons from opening the mail.

Vith these ends in view the invention consists in the novel construction, arrangement, and adaptation of parts, which will be hereinafter fully described and claimed.

In the drawings, Figure 1 is an envelop constructed in accordance with my invention and showing the sealing-flap open. Fig. 2 is an elevation of the envelop with the sealingfiap and its locking-tongue in their closed positions. Fig. 3 is a plan view of the envelopblank'in its open or spread condition. Fig. 4 is a transverse sectionthrough the envelop shown by Fig. 1.. Fig. 5 is a detail fragmentary view of one side flap and the pocketforming tongue, showing the reverse face thereof to" Fig. 3 and illustrating a sealingsurface on said tongue for uniting the flap securely to the body of the envelop after the blank shall have been folded.

The same letters of reference are used to indicate like and corresponding parts in each of the several figures of the drawings.

The envelop of my invention is made or stamped from a sheet of paper having the configurationshown more particularly by Fig. 3. This blank is provided with the usual end flaps Ct 17, and it is furthermore provided with the sealing-flap f and the bottom flap c. This last-named flap is provided with an integral pocket-forming tongue, which extends outwardly from the apex formed by the converging edges of the flap. This pocket-forming tongue consists of the foldable members 0 d,

l'and between these members is a crease or fold line 0, while a similar crease or fold line (2 is between the member 01 and the body of the flap 6. The flap e is furthermore provided with a slot 7t, which is produced by cutting the flap on three lines quite close to the crease 0r fold d, and the fragment produced by forming the slots h is bent or doubled over upon the flap 0, so as to constitute a lip g. The sealing-flapfis similar to ordinary envelops except that it is provided with an extended fastening tongue 2, which is adapted to be inserted through the slot 72. and to'be received in a pocket, which is produced by folding the members 0 d of the pocket tongue one upon the other, so that the member 0 will interlock with the lip g, as will presently appear. The end flap Z2 is provided with a coating of 'mucilaginous material to form a sealing edge j. A similar sealing edge Zr; is provided on the flap e, and a sealing-surface Z is provided on the flap f, all of these sealing surfaces or edges being indicated by the broken or dotted lines in Fig. 3.

In making the envelop the flap a is folded inwardly and the flap b is folded in the same manner for its edge j to overlap and be united to the inner edge of the flap (1. The member 0 of the pocket-tongue is now folded on the crease-line c, and the member at of said tongue is then folded on the line (1 in such manner that the edge of the member a will fold beneath and have interlocking engagement with the lip g. Y The flap c, with the pocket-tongue folded thereon, is now folded over the overlapping fiaps a b, so that the sealing edge 7c may be united to said flaps a b, the pocketwith a sealing-surface adapted to be united to the flaps a b at the place Where the tongue overlaps the same. The envelop is now completed, so that it is in a condition for use, and it is to be observed that the slot h is on the outer exposed face of the flap c, while the pocket lies between the flap and the body of the envelop, which body is formed by the overlapping flaps a b and the front of the envelop.

In using the improvedarticle the letter or other matter is first inserted in the envelop, and the sealing-surface Zon the flap f is then tongue being also provided on its outer face moistened. To close and seal the envelop, the fastening-tongue 2' is first thrust through the slot h, so as to be received in the pocket formed by the members 0 d of the tongue and the lip g, and then the fiapf ispressed firmly upon the flaps a b, so that the adhesive surface Z will firmly unite the flaps a bf together.

The improved construction of envelop herein shown and described has the sealing-flap adapted for union with the envelop-body, and its tongue is arranged for interlocking connection with a pocket-forming tongue, so that the fastening-tongue is not free or exposed for a malicious person to lift the edge of the sealing-flap and open the envelop by steaming the adhesive material or by other wellknown processes. It is to be observed that the operation of sealing the flap f to the envelop serves to prevent the tongue 2 from being withdrawn from the pocket without giving evidence of tampering with the envelop, thereby deterring evil-disposed persons from tampering or riding mail-matter. The envelop when sealed will remain securely closed to minimize the liability of loss of its contents, and if the envelop should be imperfectly sealed the tongue 11, fittingin the pocket, will have a tendency to keep the flap f in a closed position.

Having thus described the invention, what I claim is 1.. An envelop-blank comprising a series of foldable flaps, one of which is slotted to form a lip and is provided with a foldable pocketforuiing tongue adapted to have interlocking connection with the lip, said flap being foldable upon certain other flaps and forming a concealed pocket within the envelop, substantially as described.

2. As a new article of manufacture, an envelop comprising a body portion, the end flaps, a bottom flap, and a sealing-flap provided with a tongue, said bottom flap having a slot forming an internal lip, and also provided with a pocket-forming tongue having members foldable one upon the other and one i ED WIN THOMAS STUART.

Witnesses:

C. H. H. TAUCK, W. C. MCCREERY. 

